1. Field of the Invention
The present invention relates to a light box, more particularly, relates to a direct-lit light box comprising ultra-slim lighting panel and even-width frame design.
2. Descriptions of the Related Art
In recent years, the light boxes have been widely used in commercial places, such as factories, offices, hospitals, schools, and stores etc., for propaganda and advertising. In order to match up with different environments and purposes, conventional light boxes with the lighting panel devices are usually made in standard shapes and dimensions, which have been determined before producing.
The lighting panel devices of the conventional light boxes may be categorized into direct-lit backlight modules or edge-lit backlight modules according to light sources arrangements. Between these two kinds of backlight modules, the direct-lit backlight modules provide more uniform light compared with the edge-lit backlight modules especially for large-scale light boxes. Therefore, the direct-lit light boxes with direct-lit backlight modules are used widely.
This conventional direct-lit light box with large scale performs better light uniformity, however, occupies huge overall volume and consequently makes it difficult to transport and set up. Furthermore, light sources of the conventional direct-lit light box are light tubes or light bar, each of which can merely be turned on or off, such that the demonstration effect produced by the conventional light boxes is monotonous and can hardly meet the need for providing various visual effects.
In view of this, a revolutionary direct-lit light box with the lighting panel device, which adapts LED array as the light sources, becomes a new development trend. People skilled in this field all put their effort for the related advanced applications such as ultra-slim light boxes which provide better light uniformity and various visual effects. Besides, efficiently converting dot light sources, provided by LEDs, to a uniform surface light source in the direct-lit light boxes without utilizing any complicated and costly optical devices is another important research task in this field.
In fact, most of the commercial light box do not have local dimming or regional on/off feature, and therefore, do not incorporate control electronics therein. Generally, in order to provide flexible use, local dimming and regional on/off functions and control electronics embedded inside the light box product are necessarily required. However, it is difficult to design an even-width frame for such applications. Even the conventional light box with even-width frame design, the power adapter outlet and program switch button are hard to be located at adequate locations and can not be adapted for both portrait and landscape orientations at the same time.
As a result, the aforesaid technologies in the prior art have several disadvantages to be overcome. Accordingly, a need of providing a slim direct-lit light box which can be panelized by even-width frame designed lighting panel and can be applied for both portrait and landscape orientations still remains in the art.